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Ultra-processed foods may increase cancer risk

Study shows greater consumption leads to higher risk but research is needed to determine exact cause

Study shows greater consumption leads to higher risk but research is needed to determine exact cause

Ultra-processed foods are higher in fat and sugar. Picture: Alamy

Cancer can occur at any age but it is much more common in older people. According to the World Cancer Research Fund, about a third of cancers could be avoided by changing lifestyle. A balanced diet and avoiding tobacco use and excessive alcohol consumption are known to be important but this study explored the particular association between ultra-processed food and cancer. 

Researchers asked 104,980 participants to complete repeated 24-hour dietary records. Results showed that those with high ultra-processed food consumption had a significantly increased risk of breast cancer and cancer overall. There are various possible mechanisms for the increased risk. Ultra-processed food tends to be higher in fat and sugar and lower in fibre and micronutrients. This may lead to obesity, which is a known risk factor for breast cancer.

Ultra-processed foods such as dehydrated soups and sauces often have a high salt content, which is associated with higher rates of gastric cancer. Another possibility is that the additives in ultra-processed foods are to blame. Some additives, such as titanium dioxide, used as a whitening agent or to improve food texture, have been shown in animal studies to have carcinogenic properties. A further possibility is that contaminants migrate from the plastic packaging into the food.

More research is needed to determine exactly what in the ultra-processed food causes the increased rates of breast and other types of cancer. There is an urgent need for increased taxation or marketing restrictions to encourage people to eat fresh and minimally processed foods.

Fiolet T, Srour B, Sellem L et al (2018) Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort. BMJ. 360:k322. doi: 10.1136/bmj.k322

Compiled by Ruth Sander, independent consultant in care of the older person

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